progs/trivial/tri-cull-both.c

   1 /*
   2  * Copyright (c) 1991, 1992, 1993 Silicon Graphics, Inc.
   3  *
   4  * Permission to use, copy, modify, distribute, and sell this software and
   5  * its documentation for any purpose is hereby granted without fee, provided
   6  * that (i) the above copyright notices and this permission notice appear in
   7  * all copies of the software and related documentation, and (ii) the name of
   8  * Silicon Graphics may not be used in any advertising or
   9  * publicity relating to the software without the specific, prior written
  10  * permission of Silicon Graphics.
  11  *
  12  * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF
  13  * ANY KIND,
  14  * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
  15  * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
  16  *
  17  * IN NO EVENT SHALL SILICON GRAPHICS BE LIABLE FOR
  18  * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
  19  * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
  20  * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
  21  * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
  22  * OF THIS SOFTWARE.
  23  */
  24
  25 #include <stdio.h>
  26 #include <string.h>
  27 #include <stdlib.h>
  28 #include <GL/glut.h>
  29
  30
  31 #define CI_OFFSET_1 16
  32 #define CI_OFFSET_2 32
  33
  34
  35 GLenum doubleBuffer;
  36
  37 static void Init(void)
  38 {
  39    fprintf(stderr, "GL_RENDERER   = %s\n", (char *) glGetString(GL_RENDERER));
  40    fprintf(stderr, "GL_VERSION    = %s\n", (char *) glGetString(GL_VERSION));
  41    fprintf(stderr, "GL_VENDOR     = %s\n", (char *) glGetString(GL_VENDOR));
  42
  43    glClearColor(0.0, 0.0, 1.0, 0.0);
  44    glCullFace(GL_FRONT_AND_BACK);
  45    glEnable(GL_CULL_FACE);
  46
  47 }
  48
  49 static void Reshape(int width, int height)
  50 {
  51
  52     glViewport(0, 0, (GLint)width, (GLint)height);
  53
  54     glMatrixMode(GL_PROJECTION);
  55     glLoadIdentity();
  56     glOrtho(-1.0, 1.0, -1.0, 1.0, -0.5, 1000.0);
  57     glMatrixMode(GL_MODELVIEW);
  58 }
  59
  60 static void Key(unsigned char key, int x, int y)
  61 {
  62
  63     switch (key) {
  64       case 27:
  65         exit(1);
  66       default:
  67         return;
  68     }
  69
  70     glutPostRedisplay();
  71 }
  72
  73 static void Draw(void)
  74 {
  75    glClear(GL_COLOR_BUFFER_BIT);
  76
  77
  78
  79    glBegin(GL_TRIANGLES);
  80    glColor3f(.8,0,0);
  81    glVertex3f( 0.93,  0.9, -30.0);
  82    glColor3f(0,.9,0);
  83    glVertex3f(-0.93,  0.0, -30.0);
  84    glColor3f(0,0,.7);
  85    glVertex3f( 0.93, -0.8, -30.0);
  86    glEnd();
  87
  88    glFlush();
  89
  90    if (doubleBuffer) {
  91       glutSwapBuffers();
  92    }
  93 }
  94
  95 static GLenum Args(int argc, char **argv)
  96 {
  97     GLint i;
  98
  99     doubleBuffer = GL_FALSE;
 100
 101     for (i = 1; i < argc; i++) {
 102         if (strcmp(argv[i], "-sb") == 0) {
 103             doubleBuffer = GL_FALSE;
 104         } else if (strcmp(argv[i], "-db") == 0) {
 105             doubleBuffer = GL_TRUE;
 106         } else {
 107             fprintf(stderr, "%s (Bad option).\n", argv[i]);
 108             return GL_FALSE;
 109         }
 110     }
 111     return GL_TRUE;
 112 }
 113
 114 int main(int argc, char **argv)
 115 {
 116     GLenum type;
 117
 118     glutInit(&argc, argv);
 119
 120     if (Args(argc, argv) == GL_FALSE) {
 121         exit(1);
 122     }
 123
 124     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 125
 126     type = GLUT_RGB;
 127     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
 128     glutInitDisplayMode(type);
 129
 130     if (glutCreateWindow("First Tri") == GL_FALSE) {
 131         exit(1);
 132     }
 133
 134     Init();
 135
 136     glutReshapeFunc(Reshape);
 137     glutKeyboardFunc(Key);
 138     glutDisplayFunc(Draw);
 139     glutMainLoop();
 140         return 0;
 141 }